chmod 777 test.pm
Far too permissive!
That gives every man and his dog permission to run, modify or even delete the script, if they are able to browse to the directory containing it. Much safer would be
chmod u+x test.pm
We see, and have to try to fix, the chaos that ensues when someone does an ill-considered
chmod -R 777 /some/path/with_lots_of/sub-directories
and it is a practice strongly to be discouraged.